The auditor needs to have a detailed
understanding of the production system, which
takes time. Many audit departments are active
with respect to performing systems audit work
over new application systems and, typically, this
knowledge and appropriate documentation will
be available. The information required includes
details of where the key data is stored and how the files and data tables are designed and built. Another challenge is staying
up-to-date on systems changes. As changes are made to the production
system, vendor supplied release notes and the impacts of these changes must
be analyzed to ensure the CAATs design continues to use and test appropriate
data. Lastly, all downloaded information used for CAATs purposes must be
checked against production data to ensure completeness and accuracy.